Influenza, or the flu, can present similar symptoms to many other upper and lower respiratory infections. This can make it difficult, even impossible, to diagnose the flu based on symptoms alone. Dr. Patel, can you tell us how the flu is diagnosed?
Certainly, Dr. Flemings. There are a number of laboratory tests available to detect influenza viruses. All of these tests are done by swabbing the nose or back of the throat and sending the swab for testing.
The most common flu tests are called rapid influenza diagnostic tests, or RIDTs. RIDTs work by detecting antigens, which are the parts of the virus that stimulate an immune response in the body. These tests can provide results within 10 to 15 minutes, but are not as accurate as other flu tests.
Other flu tests are called rapid molecular assays. These tests detect genetic material of the flu virus, and they are more accurate than RIDTs. Results from these tests typically take 15 to 20 minutes.
There are other flu tests that are even more accurate, but these are usually only available in specialized laboratories. Results for these tests make take one hour or more.
It's important to note that most people with flu symptoms don't require testing because the test results aren't likely to change treatment strategies. However, for certain populations, such as pregnant women and people with weakened immune systems, an accurate diagnosis of the flu can be helpful in planning the best treatment.